17. Do the results of this study suggest that Harley just guessing is a plausible explanation
for Harley picking the correct cup 9 out of 10 times?
Summarizing your understanding
18. To make sure that you understand the coin flipping chance model fill in the following
table indicating what parts of the real study correspond to the physical (coin-flipping)
simulation.
Table 1.2: Parallels between real study and physical simulation
Coin flip
=
Heads
=
Tails
=
Chance of Heads = 1/2 =
One repetition
=
one set of ___ simulated attempts by Harley
The 3S Strategy
We will call the process of simulating could-have-been statistics under a specific chance model
the 3S Strategy. After forming our research conjecture and collecting the sample data, we will
use the 3S strategy to weigh the evidence against the chance model. This 3S Strategy will
serve as the foundation for addressing the question of statistical significance in Step 4 of the
Statistical Investigation Method.
3S Strategy for Measuring Strength of Evidence
1. Statistic: Compute the statistic from the observed sample data.
2. Simulate: Identify a âby chance aloneâ explanation for the data. Repeatedly simulate values
of the statistic that could have happened when the chance model is true.
3. Strength of evidence: Consider whether the value of the observed statistic from the
research study is unlikely to occur if the chance model is true. If we decide the observed statistic
is unlikely to occur by chance alone, then we can conclude that the observed data provide
strong evidence against the plausibility of the chance model. If not, then we consider the chance
model to be a plausible (believable) explanation for the observed data; in other words what we
observed could plausibly have happened just by random chance.
Letâs review how we have already applied the 3S strategy to this study.
19. Statistic. What is the statistic in this study?
20. Simulate. Fill in the blanks to describe the simulation.
June 27, 2014
MAA PREP workshop
14